Secession and the Limits of Self-Determination

Can part of a country leave? Most constitutions say no or are silent, while international law recognizes self-determination but also protects existing borders. Canada offers an influential answer. After Quebec's narrow 1995 referendum, the Supreme Court of Canada ruled in 1998 that Quebec had no right to secede unilaterally, but that a clear majority on a clear question would oblige the rest of Canada to negotiate. Parliament then passed the Clarity Act in 2000.

The UK and Scottish governments agreed the terms of Scotland's 2014 referendum in advance. Czechoslovakia split peacefully into the Czech Republic and Slovakia on 1 January 1993 without a referendum, while South Sudan became independent in 2011 after a referendum agreed in a peace deal. By contrast, the US Supreme Court held in Texas v. White (1869) that states could not leave the union. Ethiopia's 1995 constitution is unusual in granting an explicit right of secession.